Psychometric Properties of the WHOQOL-BREF Questionnaire among Disabled Students in Malaysian Higher Learning Institutions

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1 Applied Research Quality Life DOI /s Psychometric Properties of the WHOQOL-BREF Questionnaire among Disabled Students in Malaysian Higher Learning Institutions Nur Fatihah Abdullah Bandar & Rohana Jani & Mohd Aminul Karim Received: 16 November 2012 / Accepted: 21 May 2013 # Springer Science+Business Media Dordrecht and The International Society for Quality-of-Life Studies (ISQOLS) 2013 Abstract This study aims to evaluate reliability, internal consistency and dimensional structure of the World Health Organization Quality of Life (WHOQOL-BREF) among disabled students. The study covers 127 disabled students studying in public universities, 26 in private universities, 109 in polytechnic and 19 studying in community colleges. The World Health Organization Quality of Life Abbreviation (WHOQOL-BREF) has been used to assess QOL. The reliability and validity of the questionnaire were evaluated by Cronbach s alpha (α) and Pearson s correlation coefficients. Alpha scores greater than or equal to 0.6 are considered to denote acceptable and adequate internal consistency. Correlation matrix also showed satisfactory results in all domains. Factor analysis was carried out using the principal components method with varimax rotation to examine the dimensional structure of the questionnaire. This study has provided some preliminary evidence of the reliability and validity of the WHOQOL-BREF to be used for evaluating quality of life among disabled students. Keywords Quality of life. Disabled students. Malaysian higher learning institutions. Reliability. Validity N. F. Abdullah Bandar (*) : M. A. Karim Asia-Europe Institute, University of Malaya, Kuala Lumpur, Malaysia fatihah1984@gmail.com M. A. Karim mdaminulkarim1967@gmail.com R. Jani Faculty of Economics and Administration, University of Malaya, Kuala Lumpur, Malaysia rohanajani@gmail.com

2 N.F. Abdullah Bandar et al. Abbreviations QOL WHOQOL-BREF Quality of Life The World Health Organization Quality of Life Abbreviation There are many published literature on quality of life (QOL) measures but there is still a lack of consensus among researchers about its definition and this is reflected in the choice of items for their instruments (Skevington et al. 2004). Quality of life has been defined by the World Health Organization (WHO) as an individual s perception of their position in life in the context of the culture and value systems in which they live and in relation to their goals, expectations, standards, and concerns (WHO 1996;5). It is a broad-ranging concept incorporating, in a complex way, the person s physical health, psychological state, level of independence, social relationships, personal beliefs, and their relationship to salient features of the environment. People with disabilities in Malaysia can be considered as one of the most vulnerable minority groups in the Malaysian population. According to WHO, 7 % of the population in any country suffers from disability and around 2 % would need some form of rehabilitation services (WHO 2011). The WHOQOL instrument which was developed collaboratively in more than 15 cultural settings over several years and has been tested in 37 field centres; its psychometric properties has been found to be satisfactory in some countries (Yao et al. 2002; Lijiang Li et al. 2004; Usefy et al. 2010; Tsutsumi et al. 2006). Therefore, it may be possible to use it to assess variations in QOL of disabled students. Validation of the WHOQOL-BREF in terms of reliability, internal consistency and discriminant validity has attracted the attention of researchers. But this research yielded different results. Most of the studies were conducted in countries with different cultures and languages (Usefy et al. 2010; Lijiang Li et al. 2004; Webster et al. 2010). Some scholars have tried to confirm whether their observed data represent the original structure prescribed by the WHOQOL-group using confirmatory factor analysis (CFA) (Yao et al. 2002). As a developing nation, Malaysia is committed to the citizens well-being as well as to the improvement of quality of life. As such, this study proposes to use the WHOQOL-BREF, a short version of the WHOQOL-100 to assess disabled students quality of life. Although there are several Quality of life measures available for the disability groups (Ferrans and Powers 1985; Cummins 1997), the WHOQOL-BREF has some advantages for assessing QOL of disabled students. First, the WHOQOL- BREF is a well-established cross-cultural QOL measurement and second it was developed for generic use. In Malaysia, previous studies that adopted the WHOQOL-BREF mainly focus on several groups particularly different illness such as people with HIV+/AIDS, chronic schizophrenia patients, cancer patients and asthma patients (Hasanah and Razali 1999; Mubarak et al. 2003; Wan Puteh et al. 2009; Sararaks et al. 2001). However, few studies have reported on the psychometric properties as given in the WHOQOL- BREF. In view of the prevailing gap, this study is designed to examine the psychometric properties of the WHOQOL-BREF in terms of reliability and validity, item scale correlation matrix and dimensional structure of disabled students currently studying in Malaysian Higher Learning Institutions. This is a preliminary effort to

3 Psychometric Properties of the WHOQOL-BREF Questionnaire benefit ourselves of the advantages of a measure of quality of life which is easy and valid such as WHOQOL-BREF. Methods Participants A cross-sectional study design was used in this study covering a total of 281 disabled students currently pursuing their studies in Malaysian Higher Learning Institutions (public universities, private Universities, polytechnics and community colleges). Data were collected through face to face interviews using WHOQOL-BREF instrument. The participants were interviewed after being given a full briefing on the purpose of the study and taking their consent to participate in the study. Instrument The WHOQOL-BREF is available in more than 40 languages including Malay version. In this study, we sought the approval of the WHOQOL Group and used a Malay version of the instrument. As it was a self-reporting questionnaire, the participants could answer the questions on their own. However, for visually impaired students, researcher assisted the participants by reading out the questions while a Sign interpreter assisted hearing impaired students answering questions. The WHOQOL-BREF consisting of four domains: physical health (7 items), psychological health (6 items), social relationships (2 items) and environment (8 items) (WHO 1998). The physical health domain includes items on pain and discomfort, energy and fatigue, sleep and rest, dependence on medication, mobility, activities of daily living and working capacity. The psychological domain measures positive feelings, spirituality, thinking & learning, body image, self-esteem and negative feeling. The social relationships domain contains questions on personal relationships and social support. The environment domain covers issues related to physical safety and security, home environment, financial resources, access to health and social care, information and skills, recreation and leisure, physical environment and transport. All scores are transformed to reflect 4 20 for each domain with higher scores corresponding to a better QOL. Items measure the degree of intensity such as how much, how completely, how satisfied as distributed across the domains. Statistical Analysis Data entry and statistical analysis were performed using SPSS software, version Reliability analysis was carried out to examine the properties of the WHOQOL-BREF measurement scale and the items that make them up. Good reliability was found among the 23 questions of WHOOQL-BREF with Cronbach s alpha of According to Sekaran (2000), if the value of Cronbach s alpha reliabilities is less than 0.6, they are considered as poor, if the value is in 0.7 they are acceptable, and the reliability value above 0.8 are considered good. Therefore, the closer the Cronbach s alpha gets to 1.0 the better is the reliability. The construct validity of the domain structure was also assessed

4 N.F. Abdullah Bandar et al. by calculating Pearson s Correlation Coefficients for the relationship between each of the facet (question/item) scores and each of the four domain scores. Finally, factor analysis was carried out using the principal components method with varimax rotation to examine the dimensional structure of the questionnaire. Findings Socio-Demographic Characteristics The study covered 281 students with disabilities aged between 19 and 37 years. A majority of respondents in both groups were male (60.1 %) as compared to (39.9 %) female. Most of the participants in this survey reported their current level of study as Bachelor s Degree (49.5 %) followed by Diploma (40.9 %). Majority of respondents was from public universities (45.2 %) followed by polytechnics (38.8 %), private universities (9.3 %) and community colleges (6.8 %). Most of them are having hearing impaired (49.5 %) followed by physical disabilities (36.7 %) and visually impaired (13.9 %) (Table 1). Internal Consistency Cronbach s Alpha scores assess the internal consistency of each domain score based on the correlations between all responses to each of the questions. Alpha scores Table 1 Demographic profiles of disabled students Variables Category Frequency % Gender Male Female Age group < Current level of study Certificate Diploma Bachelor Master PhD Type of institution Public Private Polytechnic Community College Type of disabilities Hearing impaired Visual Impaired Physical impaired

5 Psychometric Properties of the WHOQOL-BREF Questionnaire greater than or equal to 0.6 are considered to denote acceptable and adequate internal consistency. The study findings indicated satisfactory alpha coefficients in all domains except for the social relationships. This domain showed similar results in validation studies in different countries and also the WHOQOL-BREF field trial reported a Cronbach s alpha less than 0.7 in this domain by (Skevington et al. 2004; Nedjatetal. 2008). This can be attributed to the small number of questions (2 items) in this domain. Although this domain had the lowest Alpha score in our dataset (0.699), it was not significantly different from the threshold value of 0.7 (Table 2). Construct Validity Pearson coefficient (r) was performed between item domains scores in the total sample of participants (281). Results demonstrated high item-domain correlations particularly between physical health and environmental domains (0.581) which may simply imply that the good environment provided to disabled students indicated better physical health condition. It implies that sleep and rest need good home environment for disabled student; pain and discomfort need access to health & social care; and mobility, activities of daily living and working capacity need accessible transport for them to move around. Moderate correlations were identified between physical health and psychological health. Ultimately, financial resources are less consumed because of dependence on medication is reduced. In order to cater for energy and fatigues, disabled students need facilities for recreation and leisure. Overall, the values confirm the construct validity of the instrument (Table 3). Low correlation range is from , moderate from and high is >0.5. Table 4 gives the results of the correlations between the facets of the WHOQOL- BREF and its four domains. The validity of the domain structure was also assessed by calculating Pearson s Correlation Coefficients for the relationship between each of the facet scores and each of the four domain scores. As it was expected, all the facets had their strongest correlations with the domains to which they had been assigned excepting facet mobility that indicated correlation 0.45 which is considered poor correlation with the domain physical health. This is due to their mobility difficulties regardless of their impairment. For example, disabled students use wheelchair and visually impaired need other persons (close friends and families) helping them to move around to attend lectures and to avail transportation services compared to non-disabled students. Dimensional Structure The Kaiser-Meyer-Olkin (KMO) resulted in a measure of sampling adequacy of 0.887, and the Bartlett s test of sphericity (χ2= , df=253, P<0.0001) indicated the Table 2 Internal consistency of WHOQOL-BREF domains as measured by Cronbach s alpha The WHOQOL-BREF domain No. of items Cronbach s Alpha Physical Health Psychological health Environment Social Relationships

6 N.F. Abdullah Bandar et al. Table 3 Pearson s correlations coefficients of WHOQOL-BREF domain and 281 disabled students Variables Physical Health Psychological Health Environmental Social relationships Physical health 1 Psychological health 0.373** 1 Environment 0.581** 0.514** 1 Social relationships 0.354** 0.535** 0.561** 1 **Correlation is significant at the 0.01 level (2-tailed) appropriateness to proceed with factor analysis. The Kaiser rule (eigenvalue greater than one) was used to determine the number of factors to be indicated. We used the varimax method to obtain orthogonal factors. As a result, four factors (physical health, psychological health, environmental and social relationships) were extracted. Using varimax rotation method, each factor tends to have either large or small loadings of any particular variable. A varimax solution yields results that make it as easy as possible to identify each variable with a single factor. A principal axis factor analysis was conducted to explore the factor structure of the WHOQOL-BREF without any prior suggestion on how many factors are there or whether they are correlated. As Table 5 shows, the percentage of explained variance of the four factors was % of the total variance, which is a good structure. The first factor explained % of the total variance and other three factors explained the remaining variance in the model. Discussion The study reported Cronbach s alpha of minimum and maximum of for four domains of the WHOQOL-BREF. Other studies have found α value ranging from (Lijiang Li et al. 2004); (Usefy et al. 2010) and (Yao 2002). Moreover, item-scale correlation matrix for the WHOQOL-BREF measures showed that all 7 items of physical health, 6 items of psychological health, 2 items of social relationships and 8 items of the environment domains had high significant correlation coefficients with their respective domains. Nevertheless, our findings are similar to others findings (Skevington et al. 2004; Nedjat et al. 2008) which reported a Cronbach s alpha less than 0.7 for social domain. The structural components of the WHOQOL-BREF were ascertained through factor analysis. Theoretically, we extracted items with Eigen values equal to or greater than 1.00 and subsequently the orthogonal rotation of the factors provided a satisfactory factor structures showing the contribution of the four factors explaining % of the total variance. Factor 1 (psychological health domain) which accounts for 34.3 % of the total variance, has a strong positive loadings on positive feelings>0.75, spirituality>0.75, thinking & learning >0.75 and moderate loadings on body image, self-esteem and negative feelings ( ). The psychological health with its maximum contribution was represented with all its 6 original items, spirituality were expected to be in their original place of psychological health. From cultural point of view, these observations are important and may be seen as indicators for social and

7 Psychometric Properties of the WHOQOL-BREF Questionnaire Table 4 Item-scale correlation matrix for the four WHOQOL-BREF measures The WHOQOL-BREF Physical Health Psychological health Environmental Social Relationships Physical health Pain and discomfort Dependence on medication or treatments Energy and fatigue Mobility Sleep and rest Activities of daily living Working capacity Psychological health Positive feelings Spiritual/religion/personal beliefs Thinking, learning, memory and concentration Bodily image and appearance Self-esteem ,490 Negative feelings Environment Physical safety Physical environment Financial resources Opportunities for acquiring new information and skills Leisure and recreation Home environment Health and social care Transport Social relationships Personal relationships Social supports *Correlations 0.45 was considered satisfactory political orientation of people towards religion. According to (WHOQOL 1998), spirituality facet (psychological domains) examines the person s personal beliefs and how these affect quality of life. This might be helping the person cope with difficulties/stress in his/her life. This facet addresses people with differing religious beliefs (e.g. Buddhists, Christians, Hindus, and Muslims). The WHO initiated an international project aiming at the development of a comprehensive QOL measurement system for healthy and non-healthy populations, suitable for comparisons across different cultures and settings (WHO 1998). Therefore, it may be possible to use this instrument to assess variations in QOL across different cultures (Nedjat et al. 2008; Lijiang Li et al. 2004). Many positive measures have been taken and research carried out in various countries recently to

8 N.F. Abdullah Bandar et al. Table 5 Loading for varimax rotated factor matrix of four factor model WHOQOL-BREF explaining % of the total variance Variable Loading Variable Loading Psychological health Physical health Positive Feelings Dependence on medication Spirituality Activities of daily living Thinking & learning Energy and fatigue Body image Sleep and rest Self-esteem Pain and Discomfort Negative feelings Environment Social Relationship Leisure & recreation Social Support Physical environment Personal relationships Physical safety Opportunities acquiring new information Financial resources develop strategies for welcoming person with disabilities into community/university life (Hussain and Bhamani (2012)); Arthur et al. 2008). These concepts are in line with Islamic principles of inclusion. Allah (God) has prescribed certain actions that develop positive characters, as well as bringing the Muslim closer to Him, thereby attaining taqwa (God consciousness). Malaysia is a multi-racial country with a population of 28.3 million of which 91.8 % are Malaysian citizens and 8.2 % are non-citizens. Malaysian citizens consist of the ethnic groups such as Bumiputera (67.4 %), Chinese (24.6 %), Indians (7.3 %) and others (0.7 %) (Department of Statistics 2013). The unique feature about Malaysia is that the multi-racial population practices various religions freely without any discrimination. Under the Federal Constitution, Islam is the official religion of Malaysia; nonetheless, freedom of worship for all religions is guaranteed. The Malay is the national language of the country. However, different ethnic groups are free to use their own dialects. Thus said, there are cultural differences between different ethnic groups. Such differences may be tied to their religions, rituals, food habits, dress code, family life etc. There is, however, unity in diversity in the Malaysian society at large. Be that as it may, people with disabilities in Malaysia can be considered as one of the most vulnerable groups across religious and ethnic groups (Kamarulzaman 2007). Historically, people with disabilities have been prey to society s misconceptions, stereotypes, labeling, and prejudices in many different ways. Such attitudes have led to exclusion, mistreatment, and deprivation of their rights to equal opportunities for education, jobs, and essential services (United Nation 2013). These concepts are in accord with Islamic principles of inclusion. Islam has a unique view on spirituality, as it encompasses all aspects of a Muslim s life. Spirituality, as emphasized in Islam, as a case in point, is the total submission to God for sustenance, happiness, positive feelings and so on; such spirituality overshadows the

9 Psychometric Properties of the WHOQOL-BREF Questionnaire worldly worries in one s life and contributes to happiness, dependability in the Creator, and mental peace and stability. Such triggers, to a great extent, contribute in mitigating the bodily or economic handicaps. Through spirituality stress is greatly overcome since one submits himself fully to the fait accompli as ordained by God. However, God also ordains one to put his best to attain a decent and dignified living in the world. Islam asks for harmonization between material and spiritual life of a person. And one who succeeds in attaining this synthesis achieves maximum satisfaction and happiness. Islam, in a similar vein, also calls for peace both within and without or individually and collectively. Conclusion The WHOQOL-BREF questionnaire is a brief and useful instrument to measure quality of life. Our observations add to the body of evidence that the WHOQOL- BREF has a good reliability, internal consistency, construct validity and dimensional structure for use in Malaysia. The WHOQOL-BREF showed results of high reliability and validity, therefore, the WHOQOL-BREF is a suitable instrument for evaluating quality of life among disabled students groups. Nonetheless, it is hoped that the results of QOL investigations will be suitable for use in the societal peace, development, and harmony in general. References Arthur, D., Tong, W., Chen, C., Hing, A., Sagara-Rosemeyer, M., Kua, E., et al. (2008). The validity and reliability of four measures of gambling behaviour in a sample of singapore university students. Journal of Gambling Studies, 24(4), Cummins,R.A. (1997). comprehensive quality of life scale-adult. School of Psychology. Deakin University. Department of Statistics (2013). Retrieved May 6,2013, from index.php?lang=en Ferrans, C., & Powers, M. (1985). Quality of life index: development and psychometric properties. Advances in Nursing Science, 8, Grace Yao, C. W. C., Cheng-Fen, Y., & Wang, J.-D. (2002). Development and verification of validity and reliability of the WHOQOL-BREF Taiwan version. Journal of the Formosan Medical Association, 101, Hasanah, C. I., & Razali, M. S. (1999). The pilot study of WHOQOL-100 (Malay version). The Malaysian Journal of Medical Sciences, 6, Hussain, N., & Bhamani, S. (2012). Development of the student university satisfaction scale: reliability and validity. Interdisciplinary Journal of Contemporary Research in Business, 4(3), Kamarulzaman, K. (2007). Adult learning for people with disabilities in Malaysia: provisions and services. The Journal of Human Resource and Adult Learning, 3(2). Lijiang Li, D. Y., Xiou, S., Zhaou, X., & Xiou, L. (2004). Psychometric properties of the WHOQOL-100 in patients with chronic diseases and their caregivers in China. Buletin of World Health Organization, 82(7). Mubarak, A. R., Baba, I., Chin, L. H., & Hoe, Q. S. (2003). Quality of life of community-based chronic schizophrenis patients in Penang, Malaysia. The Australian and New Zealand Journal of Psychiatry, 37, Nedjat, S., Montazeri, A., Holakouie, K., Mohammad, K., & Majdzadeh, R. (2008). Psychometric properties of the Iranian interview-administered version of the World Health Organization s Quality of Life Questionnaire (WHOQOL-BREF): a population-based study. BMC Health Services Research, 8(61). Sararaks, S., Rugayah, B., Azman, A. B., Karuthan, C., Low, L. L. (2001). Quality of Life How Do Malaysian Asthmatics Fare? Medicine Journal Malaysia 56(3).

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